This invention relates to telecommunications systems, in general, and to a method and system for controlling transmission and acceptance of messages by a telecommunications device, in particular.
Telecommunications systems frequently comprise telecommunications devices programmed to automatically send and receive messages under various conditions. Telematics systems (for example (e.g.), General Motors Corporation""s ONSTAR(copyright) system and Ford Motor Company""s RESCU(copyright) system) are examples of such telecommunications systems. Telematics generally refers to an emerging area of automotive/transportation communications technology that combines wireless voice and data to provide location-specific security, information, productivity and/or in-vehicle entertainment services to drivers and passengers. The typical telematics system includes a number of in-vehicle telematics devices that are connected wirelessly to a central service center. The in-vehicle telematics device typically includes various vehicle inputs that receive data relating to vehicle conditions (e.g., engine status, wiper status, air bag status, vehicle speed, et cetera (etc.)), an input to receive information relating to vehicle position (e.g., a Global Positioning System (GPS) receiver or GLObal NAvigation Satellite System (GLONASS) receiver), and a data/cellular transceiver. The in-vehicle device communicates location-specific information to the service center, and in turn the service center communicates with each in-vehicle device to control the in-vehicle device and deliver telematics services to the driver and/or passengers via a cellular telephone.
Message filters and message triggers facilitate such automated communications by telecommunications devices. Message triggers control the transmission of messages by the telecommunications device by defining the conditions under which a message will be transmitted by the device. Message filters define the conditions under which a message will be accepted by the device. For example, telematics systems utilize message triggers and message filters to facilitate automated communications between many vehicle-installed telematics devices and a service center. Telematics devices are typically programmed with various message triggers and filters associated with conditions under which the device will transmit and accept messages to and from the service center.
The telematics function of compiling traffic information collected from vehicles having telematics devices provides an example of the use of message triggers and filters. For example, telematics devices installed on vehicles can be instructed by use of message triggers to send messages to a service center if the vehicle exceeds a certain speed or drops below a certain speed. By receiving such messages from various vehicles traveling in an area, the service center can compile data relating to traffic conditions in the area. Through the use of message filters, the service center can provide instructions via messages to certain on-board telematics devices. On-board devices having data inputs satisfying certain specified conditions will accept a message transmitted by the service center, while telematics devices installed in other vehicles will filter the message so as not to process or respond to it.
Telecommunications functions often require filters or triggers that are based on complex logical and arithmetic comparisons of combinations of two or more conditions. Thus far, expressions defining combinations of conditions that will initiate communications have generally been preprogrammed into the telecommunications device. Configuration of the filters and triggers has typically been handled by instructing the device to apply one or more factory-programmed expressions.
The major shortcoming of such systems is that they are limited by the preprogramming of the device. Expressions defining various combinations of filters or triggers that will initiate communications must be anticipated and programmed into the telecommunications device before it is deployed. These preprogrammed expressions generally cannot be readily updated because the devices typically communicate using narrow-bandwidth signaling channels. As such, the devices must be brought to a service center to be reprogrammed if the desired combinations of conditions covered by the programmed expression need to be modified. For many telecommunications functions, there is a great need for a system that can be continuously reconfigured with various logical combinations of message filters or triggers from a remote location. For example, information desired from a telematics device reporting traffic information may vary widely depending upon a number of factors, such as, the vehicle""s location or speed, the time of day, etc. For example, it may be desirable for telematics devices installed on vehicles traveling on different roadways to have different vehicle speed triggers corresponding to the particular roadway or traffic condition. For such applications, it is particularly desirable to have a flexible telematics device that can be continuously reconfigured using message triggers and filter combinations to transmit and accept messages under varying circumstances. However, it is impractical to require deployed telematics devices to be returned to a service center for reprogramming in order to reconfigure message triggers and filters.
Accordingly, a need exists for a method and system for controlling a telecommunications device that allows telecommunications devices to be configured with numerous logical combinations of available filters and triggers without returning the device to a service center for reprogramming.